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PREPARATIONEM-9
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Valve guide drift
Removing and installing valve guide
Intake & Exhaust:
a: 9.5 mm (0.374 in) dia.
b: 5.5 mm (0.217 in) dia.
Valve guide reamer 1: Reaming valve guide hole
2: Reaming hole for oversize valve guide
Intake & Exhaust:
d
1: 6.0 mm (0.236 in) dia.
d
2: 10.175 - 10.196 mm (0.4006 - 0.4014 in)
dia.
Front oil seal drift Installing front oil seal
Rear oil seal drift Installing rear oil seal
(J-43897-18)
(J-43897-12)
Oxygen sensor thread cleaner Reconditioning the exhaust system threads
before installing a new A/F sensor and heated
oxygen sensor (Use with anti-seize lubricant
shown below.)
a: J-43897-18 (18 mm dia.) (0.71 in) for zir-
conia heated oxygen sensor
b: J-43897-12 (12 mm dia.) (0.55 in) for tita-
nia heated oxygen sensor
Anti-seize lubricant (Permatex 133AR
or equivalent meeting MIL specifica-
tion MIL-A-907) Lubricating A/F sensors and heated oxygen
sensor thread cleaning tool when recondition-
ing exhaust system threads
(Kent-Moore No.)
Tool name
Description
S-NT015
S-NT016
ZZA0012D
ZZA0025D
AEM488
AEM489
Revision: March 2010
2008 QX56
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EM-30
< ON-VEHICLE REPAIR >
EXHAUST MANIFOLD AND THREE WAY CATALYST
EXHAUST MANIFOLD AND THREE WAY CATALYST
Exploded ViewINFOID:0000000006055156
Removal and InstallationINFOID:0000000006055157
REMOVAL
WARNING:
Perform the work when the exhaust and cooling system have cooled sufficiently.
1. Remove the engine undercover (rear) using power tool (4WD models).
2. Remove front final drive assembly (4WD models). Refer to DLN-212, "
Removal and Installation".
3. Remove the main muffler assembly and center exhaust tube. Refer to EX-6, "
Removal and Installation".
4. Remove the front exhaust tubes. Refer to EX-6, "
Removal and Installation".
5. Remove front tires. Refer to WT-48, "
Rotation".
6. Remove fender protectors. Refer to EXT-23, "
Removal and Installation".
7. Remove the LH and RH air fuel ratio A/F sensors. • Follow steps below to remove each air fuel ratio A/F sensor.
a. Remove the harness connector of each air fuel ra tio A/F sensor, and harness from bracket and middle
clamp.
1. Air fuel ratio A/F sensor 1 (bank 2) 2. Exhaust manifold cover (bank 2) 3. Exhaust manifold (bank 2)
4. Gaskets 5. Exhaust manifold (bank 1) 6. Exhaust manifold cover (bank 1)
7. Air fuel ratio A/F sensor 1 (bank 1) A. Up B. Coated face
C. Manifold side D. Up mark Front
AWBIA0453GB
Revision: March 2010 2008 QX56
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EXHAUST MANIFOLD AND THREE WAY CATALYST
EM-31
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b. Remove the air fuel ratio A/F sensors from both LH and RH
exhaust manifolds using Tool.
CAUTION:
• Do not damage the air fuel ratio A/F sensors
• Discard any air fuel rati o A/F sensor which has been
dropped from a height of more than 0.5m (19.7 in) onto a
hard surface such as a concrete floor. Replace it with a
new one.
8. Support the engine using a suitable tool.
9. Remove the exhaust manifold (LH) (A) following the steps below.
• : Front
• B: Exhaust manifold (RH)
a. Remove the engine mounting insulator. Refer to EM-78,
"Removal and Installation".
b. Remove the exhaust manifold cover.
c. Remove the engine mounting bracket. Refer to EM-78,
"Removal and Installation".
d. Loosen the nuts in reverse order as shown using power tool.
e. Remove the exhaust manifold (LH) (A).
10. Remove the exhaust manifold (RH) (B) following the steps below.
• : Front
• A: Exhaust manifold (LH)
a. Remove the engine mounting insulator. Refer to EM-78,
"Removal and Installation".
b. Remove the exhaust manifold cover.
c. Remove the engine mounting bracket. Refer to EM-78,
"Removal and Installation".
d. Remove the oil level gauge guide. Refer to EM-33, "
Removal
and Installation".
e. Loosen the nuts in reverse order as shown using power tool.
f. Remove the exhaust manifold (RH) (B).
INSPECTION AFTER REMOVAL
Surface Distortion
• Check the flatness of each exhaust manifold flange surface using suitable tools.
• If measurement exceeds the limit, replace the exhaust manifold.
INSTALLATION
Installation is in the reverse order of removal. Tool number
: — (J-44626)
WBIA0630E
AWBIA0814ZZ
AWBIA0814ZZ
Flatness limit : 0.3 mm (0.012 in)
KBIA2504E
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EM-32
< ON-VEHICLE REPAIR >
EXHAUST MANIFOLD AND THREE WAY CATALYST
• Install new exhaust manifold gasket with the top of the triangularup mark on it facing up and its coated face (gray side) toward the
exhaust manifold side.
• Tighten the exhaust manifold nuts LH and RH in the numerical order shown. Then recheck the torque of the nuts.
- A: Exhaust manifold (LH)
- B: Exhaust manifold (RH)
- : Front
• Before installing new air fuel ratio A/F sensors, clean the exhaust system threads using suitable tool and
apply anti-seize lubricant.
CAUTION:
• Do not over tighten the air fuel ratio A/F se nsors. Doing so may cause damage to the sensor,
resulting in the MIL coming on.
KBIA2553E
AWBIA0814ZZ
Oxygen sensor thread cleaner : (J-43897-12)
Oxygen sensor thread cleaner : (J-43897-18)
Revision: March 2010 2008 QX56
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TIMING CHAINEM-45
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Removal and InstallationINFOID:0000000001538821
NOTE:
• To remove timing chain and associated parts, start with those on the LH bank. The procedure for removing
parts on the RH bank is omitted because it is t he same as that for removal on the LH bank.
• To install timing chain and associated parts, start with those on the RH bank. The procedure for installing parts on the LH bank is omitted because it is t he same as that for installation on the RH bank.
REMOVAL
1. Remove the engine assembly from the vehicle. Refer to EM-78, "Removal and Installation".
2. Remove the following components and related parts: • Drive belt auto tensioner and idler pulley. Refer to EM-13, "
Removal and Installation".
• Thermostat housing and water hose. Refer to CO-22, "
Removal and Installation".
• Power steering oil pump bracket. Refer to ST-26, "
Removal and Installation".
• Oil pan (lower), (upper) and oil strainer. Refer to EM-33, "
Removal and Installation".
• Ignition coil. Refer to EM-37, "
Removal and Installation".
• Rocker cover. Refer to EM-38, "
Removal and Installation".
3. Remove the Intake valve timing control solenoid valve cover (RH) (A) and Intake valve timing control solenoid valve cover
(LH) (B) as follows:
a. Loosen and remove the bolts as shown.
b. Cut the liquid gasket and remove the covers using Tool.
CAUTION:
Do not damage mating surfaces.
1. Camshaft sprocket (LH) bank EXH 2. Camshaft sprocket (LH) bank INT (VTC)3. Camshaft sprocket (RH) bank INT
(VTC)
4. Camshaft sprocket (RH) bank EXH 5. Front cover 6. Intake valve timing control solenoid
valve (RH)
7. Intake valve timing control solenoid valve cover (RH) 8. Intake valve timing control position
sensor (RH) 9. Intake valve timing control position
sensor (LH)
10. Intake valve timing control solenoid valve cover (LH) 11. Camshaft position
sensor (PHASE) 12 Cran kshaft pulley bolt
13. Crankshaft pulley 14. Chain tensioner cover 15. Front oil seal
16. Intake valve timing control solenoid valve (RH) 17. O-ring
18. Timing chain tension guide (RH)
bank
19. Timing chain slack guide (RH) 20. Timing chain (RH) bank 21. Timing chain (LH)
22. Chain tensioner (RH) 23. Timing chain slack guide (LH) bank 24. Timing chain tension guide (LH) bank
25. Chain tensioner (LH) 26. O-ring 27. Bracket
28. Oil pump drive spacer 29. Oil pump assembly 30. Crankshaft sprocket
A. To crankshaft B. To camshaft (LH) bank EXH C. To camshaft (LH) bank INT (VTC)
D. To camshaft (RH) bank INT (VTC) E. To camshaft (RH) bank EXH F. Apply sealant to mating side
G. Follow installation procedure
Tool number : KV10111100 (J-37228)
WBIA0798E
Revision: March 2010 2008 QX56
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CAMSHAFTEM-53
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CAMSHAFT
ComponentsINFOID:0000000001538822
Removal and InstallationINFOID:0000000001538823
NOTE:
Do not remove the engine assembly to perform this procedure.
REMOVAL
1. Remove the RH bank and LH bank rocker covers. Refer to
EM-38, "Removal and Installation".
AWBIA0101GB
1. Cylinder head RH bank2. Camshaft bracket (No. 2, 3, 4, 5) 3. Valve lifter
4. Camshaft bracket (No. 1) 5. Seal washer6. Camshaft RH bank (EXH)
7. Camshaft RH bank (INT) 8. Camshaft LH bank (INT)9. Camshaft LH bank (EXH)
10. Camshaft sprocket RH bank (EXH) 11. Camshaft sprocket RH bank (INT) (VTC)12. Camshaft sprocket LH bank (INT)
(VTC)
13. Camshaft sprocket LH bank (EXH) 14. Camshaft position sensor (PHASE) 15. O-ring
16. Cylinder head LH bank A. Follow installation procedure
Revision: March 2010 2008 QX56
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EM-68
< ON-VEHICLE REPAIR >
CYLINDER HEAD
CYLINDER HEAD
Exploded ViewINFOID:0000000006055158
Removal and InstallationINFOID:0000000006055159
REMOVAL
1. Remove the engine assembly from the vehicle. Refer to EM-78, "Removal and Installation".
2. Remove the following components and related parts: • Drive belt auto tensioner and idler pulley. Refer to EM-14, "
Drive Belt Auto Tensioner and Idler Pulley".
• Generator assembly and bracket. Refer to CHG-22, "
Removal and Installation".
• Fuel tube and fuel injector assembly. Refer to EM-40, "
Removal and Installation".
• Intake manifold. Refer to EM-26, "
Removal and Installation".
• Thermostat housing and hose. Refer to CO-22, "
Removal and Installation".
• Rocker cover. Refer to EM-38, "
Removal and Installation".
• Oil pan and oil strainer. Refer to EM-33, "
Removal and Installation".
3. Remove the crankshaft pulley, front cover, oil pump, and timing chain. Refer to EM-45, "
Removal and
Installation".
4. Remove the camshaft sprockets and camshafts. Refer to EM-53, "
Removal and Installation".
5. Remove the cylinder head bolts in reverse of order shown.
6. Remove the cylinder heads.
INSPECTION AFTER REMOVAL
Cylinder Head Bolts Diameter
1. Harness bracket 2. Engine coolant temperature sensor 3. Washer
4. Cylinder head gasket (LH) 5. Cylinder head (RH) 6. Cylinder head bolt
7. Cylinder head gasket (RH) 8. Cylinder head (LH)
KBIA2528E
PBIC0068E
Revision: March 2010 2008 QX56
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EM-82
< DISASSEMBLY AND ASSEMBLY >
ENGINE UNIT
DISASSEMBLY AND ASSEMBLY
ENGINE UNIT
Disassembly and AssemblyINFOID:0000000001538832
1. Knock sensor sub-harness 2. Knock sensor3. Cylinder block
4. Main bearing upper 5. Top ring6. Second ring
7. Oil ring 8. Crankshaft key9. Piston
10. Connecting rod 11. Snap ring12. Piston pin
13. Connecting rod bearing 14. Connecting rod bearing cap 15. Main bearing cap
WBIA0471E
Revision: March 2010 2008 QX56